"He's a bonny lad and you'll be pleased to know that he's currently preparing for life as a prop forward!" joked the Duke of Cambridge.
He went on give a little insight into life as a new parent, saying that Prince George is "at his most vocal at 3am, as you may have noticed".
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Duke and Duchess of Cambridge with Prince George on Monday
He quipped in reference to the traditional ancestral dance from the Maori people of New Zealand: "I swear I heard him doing the haka this morning.
"I hope that George doesn’t keep you up!"
William, 31, also thanked the country and its representatives for welcoming his family to the country.
"Thank you also for hosting Catherine, George and me during our time in New Zealand," he continued.
The family enjoyed a playdate on Wednesday
As a devoted father and husband, he shared his joy at being in New Zealand with Kate and George.
"I cannot tell you how happy I am to be back here in God’s Own Country – as I have learned to call it – and this time with my wife and son," the charming British royal went on.
"On this visit, I have no doubt that it will be Catherine – and not just me – who falls for New Zealand."
The couple didn't take George to unveil a portrait of the Queen
Once William had concluded his speech, the portrait of the Queen was unveiled, showing the monarch in a royal blue dress with her trademark pearl necklace and a silver fern brooch.
It was painted by New Zealand artist Nick Cuthell - who also did the cast members of The Hobbit - and will remain on permanent public display in the New Zealand Portrait Gallery.